1. Field of the Invention
Embodiments of the present invention generally relate to systems and methods for upgrading hydrocarbons. More particularly, embodiments of the present invention relate to systems and methods for upgrading de-asphalted oil in a fluidized catalytic cracking unit.
2. Description of the Related Art
Conventional refinery distillation processes separate light hydrocarbon compounds from feedstocks, leaving a large volume of residual oil that is primarily heavy hydrocarbons. Solvent de-asphalting (“SDA”) processes have been used to treat the heavy hydrocarbons with a solvent to generate asphaltenic and de-asphalted oil products (“DAO”). The asphaltenic and DAO products are typically treated and/or processed into useful products.
DAO can be economically attractive when downstream treatment facilities, such as hydrotreating or fluidized catalytic cracking (“FCC”), are adequately designed to process the DAO generated when treating the heavy hydrocarbons. However, hydrocracking the DAO requires a capital-intensive, high-pressure system to process the large quantity of DAO, especially when intermediate products such as diesel, gas oil, and/or kerosene are preferred.
Additionally, DAO products derived from a vacuum distillation process can be too viscous for efficient catalytic cracking in an FCC system. Furthermore, the boiling point of a significant portion of the DAO can be above normal riser-reactor operating temperatures of conventional FCC systems. This can lead to excessive production of coke, poor yield selectivity, and the potential for coke deposition on the components of the FCC system.
There is a need, therefore, for improved systems and methods for upgrading DAO in an FCC system.